[1] Decimal totals are calculated by converting the time (hh:mm) totals. The decimal totals are not calculated by adding the daily decimal hours. The sum of daily decimal hours might not equal calculated total decimal hours for a pay period because of rounding differences. People are usually paid on the weekly total of hh:mm and that is the number that would be converted to a decimal total.

[2] hh:mm is time in hours and minutes. 8:15 is 8 hours and 15 minutes.

[3] Decimal is time in hours only with a fractional decimal part. 8.25 is 8.25 hours and since 0.25 is one quarter of an hour, 0.25 is equal to 15 minutes. So the decimal representation of time of 8.25 hours is equivalent to 8 hours and 15 minutes. 8.25 hours = 8:15